Method of making a precious metal postage stamp

ABSTRACT

A method of making precious metal postage stamps which can be very finely worked in intricate designs without creating any cracks or holes in the metal. The method includes the steps of laminating a precious metal sheet in a plurality of different rolling-mills, manually beating the laminated sheet with a hammer, this beating being carried out such that one or more hammers are moved along a trapezoidal path during the beating operation, coating one side of the sheet with an adhesive agent and forming a relief design in the sheet.

nited States Patent 1191 11] 3,833,990 Boccard Sept. 10, 1974 METHOD OFMAKING A PRECIOUS 1,103,222 7/1914 Rauskolb 161/213 x METAL POSTAGESTAMP FOREIGN PATENTS OR APPLICATIONS [76] Inventor: Madeleine Boccard,25 rue de 19,821 8/1898 Great Britain .L 29/199 lArquebruse CPI-1204,Geneve, Switzerland Primary Examiner-Charles W. Lanham AssistantExaminer-D. C. Reiley, Ill

[22] Ffled' 1974 Attorney, Agent, or Firm-Raymond A. Robic; Arthur [2l]Appl. No.: 433,522 Schwartz; Peter G. Mack 1 Related US. ApplicationData [63] Continuation-impart of Ser. No. 246,524, April 24, [57]ABSTRACT 1972, abandoned A method of making precious metal postagestamps which can be very finely worked in intricate designs [52 US. Cl29/412, 29/199, 29/5274, without creating y cracks or holes in themetal- The 72/7 161/213 method includes the steps of laminating aprecious 51 im. c1. 823p 17/00 metal Sheet in a plurality of differentrolling-mills, 58 Field of Search 29/199, 527.4, 412; 72/76; manually bg the laminated sheet with a hammer, 15 277 3 4 33 1 1/213 this beatingbeing carried out such that one or more hammers are moved along atrapezoidal path during 5 R f e i d the beating operation, coating oneside of the sheet UNITED STATES PATENTS with an adhesive agent andforming a relief design in 146,001 12/1873 Hastings 29/199 the Sheet597,012 1/1898 Michalk 29/199 x v3 Claims, N0 Drawings METHOD OF MAKDJGA PRECIOUS WTAL CROSS REFERENCE TO RELATED APPLICATION This is acontinuation-in-part application of copending US. application Ser. No.246,524, Madeleine Boccard, filed Apr. 24, 1972, now abandoned.

BACKGROUND OF THE INVENTION SUMMARY OF THE INVENTION The presentinvention proposes a method of manufacture of an unbreakable postagestamp of extreme flexibility. Stamps produced according to the method ofthe invention can be very finely worked with an intricate design withoutany cracks or holes appearing in the metal. The method by which this isaccomplised includes the steps of alternately laminating sheets ofprecious metal in different rolling-mills and hand beating the laminatedsheets with one or more hammers. This beating is carried out in atrapezoidal pattern, i.e., one or more hammers are moved along atrapezoidal path during the manual beating operation. This manner ofbeating influences the structure of the sheet giving it greatflexibility. The processed sheets, which may vary in thickness frombetween 0.05 mm to 0.20 mm, are then coated with glue, stamped out anddivided into stamps of a predetermined size.

DETAILED DESCRIPTION In the process of the present invention bars orslabs of precious metal, e.g., gold, are transformed into fine sheets.To do this, machines for laminating precious metal are used. Inthemselves, however, existing machines are unsuitable in the field ofprecious metal postage stamp production, since such machines do notconfer to the metal sheets the extreme flexibility, which is necessary.It is for this reason that manual labor is used to give the sheets ofprecious metal their essential flexibility.

The procedure described hereafter specifies a sheet of gold, however thesame method can be applied to other precious metals such as platinum andsilver.

To an ingot of pure gold are added copper, nickel and silver inproportions calculated to give the desired stamp color; e.g., paleyellow, lemon color, pale green, dark green, etc. The mixture is heatedto 1200 C or 1300 C and a new ingot is made which will measure, forexample, 15 cm in length, 35 cm in width and 0.7 cm or 0.8 cm inthickness. After re-heating, the ingot is passed through a first rollingmill, is heated again to effect softening and is then laminated a secondtime. The ribbon of gold lengthens by 4 to 6 meters each time it goesthrough the rolling mill and the process is continued until the ribbonis 17 to 18 meters long. The metal ribbon is then folded into 16 equalparts and fed into a third rolling mill which cuts it up into squaresmeasuring 10 cm on each side. Cut into four pieces, the sheets of goldare placed one at a time between the pages of some sort of notebook. Therelative thickness of the sheet, measured in lengths of milimeters issufficient to allow it to be rough-rolled into squares of 10 cm by 10cm.

From this stage on, machines can no longer be used. Instead, the sheetsof gold are hand beaten with one or more hammers to give the requiredflexibility. Preferably, a plurality of hammers weighing 3,250 kg, 6.500kg and 9 kg, respectively, are used to beat the sheets of gold. Aftereach beating operation the gold is alternately heated, beaten again, andheated again. During the heating process the workman places the gold ona flat granite slab. The strokes of the hammer must be carefully appliedwith the desired force in a wedge shape or, more precisely, in atrapezoidal pattern (i.e., in the form of a swallows tail). This type ofbeating produces a molecular arrangement in the metal resulting in theexact structure necessary for excellent flexibility. Thus, the metalsheets will be suitable for making postage stamps.

In the foregoing description of the beating operation, it is to beunderstood that the expressions wedge shape and trapezoidial pattern donot refer to the shape of the indentations left by each hammer stroke.

Rather, these terms refer to the fact that the beating is carried outsuch that the hammers are moved along a trapezoidal path during thebeating operation. For example, the beating may first be carried out ina direction corresponding to a parallel side of a trapezoid. The beatingthen continues in a direction corresponding to one of the inclined sidesof the trapezoid and thence, in a direction corresponding to the otherparallel side. Finally, the beating is carried out in the direction ofthe other inclined side, whereupon the starting point will be reached.

The gold sheets thus obtained vary in thickness between 0.05 mm and 0.20mm. The gold beater works the sheet once more before it undergoes thestamping process which gives it its final aspect. The stamping which,for example, may produce a design in relief causes tensions in themetal, and this is the reason why it is extremely important that themetal be very flexible and pliable in order to avoid cracking orbreaking. Heretofore it has not been possible to attain the proper metalcharacteristics by practicable, known methods.

Applicant has discovered, however, that by using the abovedescribedbeating process the problems experienced in known methods of preciousmetal stamp production are overcome. Specifically, the above describedbeating process alters the structure of the precious metal sheets suchthat a detailed relief design can be applied thereto without theformation of cracks or small holes.

If the formation of the final, relief design is carried out (by, forexample, coining, pressing or deep embossing) after the lamination stepand without the above described beating process, small holes or cracksin the stamp will result. This is so because, after lamination, thesheet of precious metal is subject to numerous internal stresses, and itexhibits uneven thicknesses and a lack of flexibility. As such, thesheet is not adapted to sustain an additional operation which wouldcreate substantial new stresses.

The applicant has discovered that the above described process ofmanually beating the metal in a trapezoidal pattern is particularlyeffective in relieving the stresses and in producing a precious metalsheet which is uniform and flexible. The resulting sheet, then, isideally suited for a final coining or embossing step which can beperformed without the usual formation of cracks and/or holes.

When the sheets of gold, silver or platinum have attained the correctthickness and flexibility, they are then coated with glue. This glue isapplied from a sheet of gummed paper with the result that the reverseside of the metal is adhesive in exactly the same manner as an ordinarypaper postage stamp.

Next, the sheet is stamped either into single stamps or into a block ofseveral stamps. All that remains to be carried out is the perforation,the number of perforaof distinguished individuals or in commemoration ofthe anniversaries or dates of independence of certain countries.

What is claimed:

1. A method of making a postage stamp of precious metal comprising thesteps of:

a. laminating the precious metal in rolling mills to form a preciousmetal sheet;

b. manually beating the precious metal sheet with a hammer, the beatingbeing carried out such that the hammer is moved along a trapezoidal pathduring the beating;

c. coating one side of the precious metal sheet with an adhesive agent;and

d. forming a relief design in the precious metal sheet.

2. A method as defined in claim 1 wherein the precious metal sheet iscut into a plurality of postage tions being indicated by the customer.The edges of Stamps after formation of the relief design each stamp mayalso turned back in a roof-like slope.

3. A method as defined in claim 1 wherein: a. the beating step iscarried out more than once; and

b. the laminated sheet is heated after each beating step.

1. A method of making a postage stamp of precious metal comprising thesteps of: a. laminating the precious metal in rolling mills to form aprecious metal sheet; b. manually beating the precious metal sheet witha hammer, the beating being carried out such that the hammer is movedalong a trapezoidal path during the beating; c. coating one side of theprecious metal sheet with an adhesive agent; and d. forming a reliefdesign in the precious metal sheet.
 2. A method as defined in claim 1wherein the precious metal sheet is cut into a plurality of postagestamps after formation of the relief design.
 3. A method as defined inclaim 1 wherein: a. the beating step is carried out more than once; andb. the laminated sheet is heated after each beating step.